Add logs for batch request (#228)

* add logs for batch request

* add metric

jsonrpc/metrics/metrics_xlayer.go

@@ -16,6 +16,7 @@ var (
 	requestAuthCountName        = requestPrefix + "auth_count"
 	requestAuthErrorCountName   = requestPrefix + "auth_error_count"
 	requestRelayFailCountName   = requestPrefix + "relay_fail_count"
+	requestBatchSizeName        = requestPrefix + "batch_size"
 
 	wsRequestPrefix             = prefix + "ws_request_"
 	requestWsMethodName         = wsRequestPrefix + "method"
@@ -38,6 +39,10 @@ var (
 			Name: lastRawGasPriceName,
 			Help: "[JSONRPC] raw gas price",
 		},
+		{
+			Name: requestBatchSizeName,
+			Help: "[JSONRPC] batch request size",
+		},
 	}
 
 	histogramVecs = []metrics.HistogramVecOpts{
@@ -192,3 +197,8 @@ func RequestAuthErrorCount(tp RequestAuthErrorType) {
 func RequestRelayFailCount(method string) {
 	metrics.CounterVecInc(requestRelayFailCountName, method)
 }
+
+// RequestBatchSize increments the batch requests count
+func RequestBatchSize(batchSize int) {
+	metrics.GaugeSet(requestBatchSizeName, float64(batchSize))
+}

jsonrpc/server.go

@@ -369,7 +369,7 @@ func (s *Server) handleBatchRequest(httpRequest *http.Request, w http.ResponseWr
 	}
 
 	responses := make([]types.Response, 0, len(requests))
-
+	var methods string
 	for _, request := range requests {
 		if !methodRateLimitAllow(request.Method) {
 			responses = append(responses, types.NewResponse(request, nil, types.NewRPCError(types.InvalidParamsErrorCode, "server is too busy")))
@@ -384,7 +384,10 @@ func (s *Server) handleBatchRequest(httpRequest *http.Request, w http.ResponseWr
 		}
 		responses = append(responses, response)
 		metrics.RequestMethodDuration(request.Method, st)
+		methods += request.Method + ","
 	}
+	metrics.RequestBatchSize(len(responses))
+	log.Infof("Batch request handled: %s total: %d", methods, len(responses))
 
 	respBytes, _ := json.Marshal(responses)
 	_, err = w.Write(respBytes)